Replying to [comment:4 Lemming]:
A unification with the WARNING pragma looks like a good idea to me. I
#11796: Warn about unwanted instances in a modular way -------------------------------------+------------------------------------- Reporter: Lemming | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #11219 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Lemming): Replying to [comment:5 RyanGlScott]: think I did not consider it, because currently warnings cannot be grouped. But if WARNINGs can be grouped we could re-use this capability for `instance` warnings.
`WARNING`s can be grouped, actually:
{{{#!hs hello = "hello" world = "world"
{-# WARNING hello, world "Beware" #-} }}}
I see, the grouping works the other way round to what I had in mind. See below.
Indeed. In fact, there could be two different private modules in the same package that export two functions with the same name, or two instances with the same tag. I can't think of a better way to tell them apart, can you?
I would consider it a feature, not a bug. Every warning tag should represent a group not a single object. If multiple objects get the same tag, you can enable and disable and error-convert multiple warnings via one tag. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11796#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler